The field of art to which this invention pertains is the production of high quality lube oil blending stock from atmospheric fractionation residue and waste lubricant.
There has always been a demand for high quality lube oil blending stock and recently there is a steadily increasing demand for technology which is capable of reclaiming and rerefining waste lubricants. Previous techniques utilized to dispose of waste lubricants which are frequently contaminated with halogenated organic compounds and other heteroatomic compounds have frequently become environmentally unpopular or illegal and, in general, have always been expensive. With the increased environmental emphasis for the treatment and recycle of chlorinated organic compounds and waste lubricants, there is an increased need for the conversion of these products when they become spent and unwanted. For example, large quantities of used motor oil are generated and discarded which oil would provide a large potential supply of feedstock for the present invention while providing an environmentally responsible disposal. Therefore, those skilled in the art have sought to find feasible techniques to convert such feedstocks to provide hydrocarbonaceous product streams including high quality lube oil blending stock which may be safely and usefully employed or recycled. Previous techniques which have been employed include incineration and dumping which, in addition to potential pollution considerations, fail to recover valuable hydrocarbonaceous materials.